<template>
  <div class="todo-header">
    <input type="text" placeholder="请输入你的任务名称,按回车键确认" v-model="title" @keyup.enter="add">
  </div>
</template>
<script>
import { nanoid } from 'nanoid';
export default {
  name: 'MyHeader',
  data() {
    return {
      title: ''
    };
  },
  methods: {
    add() {
      // 校验数据
      if (!this.title.trim()) return alert('输入不能为空');
      //将用户的输入包装成一个todo对象
      const todoObj = {
        id: nanoid(),
        title: this.title,
        done: false
      };
      //通知App组件去添加一个todo对象
      this.$emit('addTodo', todoObj);
      //清空输入
      this.title = '';
    }
  }
};
</script>
<style lang="less" rel="stylesheet/less" scoped>
/*header */
.todo-header input {
  width: 560px;
  height: 28px;
  font-size: 14px;
  border: 1px solid #ccc;
  border-radius: 4px;
  padding: 4px 7px;
}
.todo-header input:focus {
  outline: none;
  border-color: rgba(82, 168, 236, 0.8);
  box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075),
    0 0 8px rgba(82, 168, 236, 0.6);
}
</style>